Fetuses are listening. And they’ll remember what they heard. Studies had shown they can hear songs and learn sounds while in the womb. Now scientists show that fetuses can learn specific words, too. And for at least a few days after they’re born, babies can still recall commonly repeated words.
This study doesn’t mean that fetuses and newborns understand those words. Rather, the study found that newborns recognize the sound patterns of certain words. But that finding suggests the ability of a fetus to learn is “much more specific than we thought,” Eino Partanen told Science News. A psychologist at the University of Helsinki in Finland, he coauthored the new study. His team’s results appeared August 26 in the Proceedings of the National Academy of Sciences.
To test a newborn’s memory, the scientists used a fake word: “tatata.” They gave 17 pregnant women in Finland, all in the final three months of pregnancy, the same assignment. At least five days per week, each mom-to-be had to play a loud recording of a woman saying the nonsense word over and over. Scientists asked the pregnant women to play the recordings twice on each of those days for four minutes.
Most times, the word sounded the same. But once in a while the recording changed: The middle “ta” was pronounced in a higher or lower pitch.
Several days after each baby’s birth, the scientists performed a test. First, they attached electrodes to the babies’ heads. (These electrodes were harmless devices that could detect electric activity in the brain.) Then each baby listened to the fake word played for it before birth. When the recording came to the changed version of the word “tatata,” the electrodes detected a surge in the baby’s brain activity.
That surge indicated that the baby was familiar with the word, Partanen said. Adults start showing similar reactions as they learn words in a new language, previous studies have shown.
The scientists also tested 16 babies who had never heard recordings of the fake word while in the womb. These babies did not show the same surge when they heard the changed version of “tatata.”
Earlier studies have used babies’ behavior — like sucking on a pacifier or turning their heads — to look for signs of learning. Importantly, this new study shows actual effects in the brain, notes Christine Moon, who did not work on the new study. She’s a psychologist at Pacific Lutheran University in Tacoma, Wash.
“We’ve had quite a bit of research on behavior and not so much on the brain,” she told Science News.
behavior The way a person or animal acts towards others, or how it conducts itself.
fetus The unborn offspring of a mammal, in particular an unborn human baby more than eight weeks after conception.
pitch (in physics) The highness or lowness of a sound, determined by the vibration that made the sound.
psychology The study of the human mind, especially in relation to actions and behavior.
womb The organ in the lower body of a woman or female mammal where offspring are conceived and in which they gestate before birth.